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Considering the economic and commercial efficiency of the beef production chain, the yield and quality of the meat produced must also be included in breeding programs. For the Nellore breed, including the polled herd, these aspects have not been much studied. The aim of this study was to estimate genetic parameters for scrotal circumference adjusted to 365 (SC365) and 450 (SC450) days of age, age at first calving (AFC), accumulated productivity (AP), stayability (STAY), longissimus muscle area (LMA), thickness of subcutaneous fat over the 12th-13th ribs (BF), thickness of subcutaneous fat over the rump (RF), and shear force measured by Warner-Bratzler shear force (WBSF) of polled Nellore cattle. Bayesian analyses were performed by adopting a linear animal model, whereas STAY analyses used the linear threshold model. Heritability estimates were 0.31 (SC365), 0.37 (SC450), 0.16 (AFC), 0.25 (AP), 0.16 (STAY), 0.30 (LMA), 0.13 (BF), 0.24 (RF), and 0.15 (WBSF), indicating moderate response to selection. Genetic and residual correlations between SC365 and SC450 were high (0.91 and 0.74, respectively), as well as the genetic correlations of AP with SC365, SC450, AFC, and STAY (0.61, 0.62, - 0.69, and 0.83, respectively). Genetic and residual correlations of WBSF with reproductive and carcass characteristics exhibited high standard deviations, however favorable. Based on the results, it is expected that in the medium term, animals with greater sexual precocity will also have greater accumulated productivity and longer permanence of females in the herd, along with superior carcass traits. However, due to the low heritabilities and small genetic associations with reproductive traits, fat thickness characteristics (BF and RF) will still require direct selection.

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Evaluar el algoritmo de segmentación tumoral de la imagen PET semiautomatizada para delinear el volumen tumoral grueso (GTV) en pacientes con cáncer cervical localmente avanzado. Material y métodos. Se evaluó retrospectivamente a 32 pacientes con cáncer cervical localmente avanzado. Se utilizó la delineación GTV basada en imagen PET semiautomatizada, utilizando un algoritmo previamente establecido (GTV2SD) y 2 métodos basados en umbrales fijos (GTV40% y GTV50%). Se calculó GTV2SD, como el píxel con el valor medio más 2 desviaciones estándar de la intensidad del hígado, y GTV40% y GTV50% con el 40% y el 50% de intensidad tumoral máxima (Tmáx), respectivamente. A continuación se compararon los volúmenes derivados con los GTV generados manualmente, utilizando RM (GTVMR). Resultados. El valor medio de GTV2SD, GTV40% y GTV50% fue de 85,3 cc; 16,2 cc y 24,1 cc, respectivamente. Se halló una buena concordancia entre GTV2SD y GTVMR (rho=0,88). GTV40% y GTV50% mostraron una menor correlación con GTVMR (rho=0,68 y rho=0,71, respectivamente). Conclusiones. Este estudio prueba de modo preliminar que la delimitación del volumen tumoral metabólico es posible utilizando las mediciones generadas informáticamente en las imágenes de 18F-FDG PET. La generación de los volúmenes tumorales basados en PET se ve afectada por la elección del nivel de umbral utilizado. El grueso del tumor metabólico calculado utilizando el píxel con el valor medio más 2 desviaciones de la intensidad del hígado (GTV2SD) guarda una mejor correlación con los volúmenes tumorales derivados de RM. El método constituye un enfoque simple y clínicamente aplicable para generar el GTV derivado del PET, para la planificación de la terapia de radiación del cáncer cervical(AU)

Objective. To evaluate a semi-automated PET-image tumor segmentation algorithm for gross tumor volume (GTV) delineation in patients with locally advanced cervical cancer. Material and methods. Thirty-two patients with locally advanced cervical cancer were retrospectively evaluated. Semi-automated PET-image-based GTV delineation was applied using a previous established algorithm (GTV2SD) and 2 fixed threshold-based methods (GTV40% and GTV50%). GTV2SD was determined as the pixel with the mean value plus 2-standard deviation of the liver intensity, and GTV40% and GTV50% with 40% and 50% of the maximum tumor intensity (Tmax), respectively. The derived volumes were then compared with the GTVs generated manually using MR (GTVMR). Results. The mean value of GTV2SD, GTV40% and GTV50% was 85.3cc, 16.2cc and 24.1cc, respectively. Good agreement was noticed between GTV2SD and GTVMR (rho=0.88). GTV40% and GTV50% showed weaker correlation with GTVMR (rho=0.68 and rho=0.71, respectively). Conclusions. This study provides preliminary evidence that metabolic tumor volume delineation is feasible using computer-generated measurements in 18F-FDG PET images. Generation of PET-based tumor volumes is affected by the choice of threshold level used. Metabolic tumor bulk calculated using the pixel with the mean value plus 2-standard deviations of the liver intensity (GTV2SD) correlates better with the MR-derived tumor volumes. The method is a simple and clinically applicable approach to generate PET-derived GTV for radiation therapy planning of cervical cancer(AU)

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OBJECTIVE: To evaluate a semi-automated PET-image tumor segmentation algorithm for gross tumor volume (GTV) delineation in patients with locally advanced cervical cancer. MATERIAL AND METHODS: Thirty-two patients with locally advanced cervical cancer were retrospectively evaluated. Semi-automated PET-image-based GTV delineation was applied using a previous established algorithm (GTV2SD) and 2 fixed threshold-based methods (GTV40% and GTV50%). GTV2SD was determined as the pixel with the mean value plus 2-standard deviation of the liver intensity, and GTV40% and GTV50% with 40% and 50% of the maximum tumor intensity (Tmax), respectively. The derived volumes were then compared with the GTVs generated manually using MR (GTVMR). RESULTS: The mean value of GTV2SD, GTV40% and GTV50% was 85.3cc, 16.2cc and 24.1cc, respectively. Good agreement was noticed between GTV2SD and GTVMR (ρ=0.88). GTV40% and GTV50% showed weaker correlation with GTVMR (ρ=0.68 and ρ=0.71, respectively). CONCLUSIONS: This study provides preliminary evidence that metabolic tumor volume delineation is feasible using computer-generated measurements in (18)F-FDG PET images. Generation of PET-based tumor volumes is affected by the choice of threshold level used. Metabolic tumor bulk calculated using the pixel with the mean value plus 2-standard deviations of the liver intensity (GTV2SD) correlates better with the MR-derived tumor volumes. The method is a simple and clinically applicable approach to generate PET-derived GTV for radiation therapy planning of cervical cancer.

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OBJETIVO GERAL: Verificar, em um grupo de mulheres submetidas à cirurgia por câncer de mama, a efetividade do tratamento do linfedema, por um período de até dois anos. OBJETIVO ESPECíFICO: Avaliar o volume do braço tratado aos 6, 12, 18 e 24 meses após o tratamento do linfedema. MÉTODO: As participantes foram atendidas em um serviço de reabilitação especializado e submetidas ao tratamento do linfedema, com drenagem linfática manual, enfaixamento compressivo funcional, orientações de autocuidado, automassagem, uso da braçadeira elástica e exercício. Pelas medidas do volume dos membros, nos períodos determinados, 36 mulheres foram avaliadas após a fase intensiva, 22 após 6 meses, 15 após 12 meses, 6 após 18 meses e 11 aos 24 meses. A adesão às estratégias de autocuidado e exercícios foi avaliada através de um questionário. Testes estatísticos foram usados para buscar correlação entre redução do linfedema e alguns fatores como idade, escolaridade, grau do linfedema, tipo de cirurgia, entre outros. RESULTADOS: Houve redução do linfedema e essa se manteve ao longo dos períodos estudados. Não houve correlação entre redução do linfedema e fatores como idade, estado civil, escolaridade, tipo de cirurgia, índice de massa corporal, grau do linfedema, radioterapia, circunferência, hipertensão arterial ou limitação articular e não houve adesão às estratégias de autocuidado com o braço, realização de exercícios, automassagem e uso de braçadeira elástica pela maioria das mulheres. CONCLUSÕES: É importante realizar novas pesquisas que analisem o papel de cada uma dessas orientações na evolução do linfedema após a fase intensiva do tratamento, de forma sistemática e controlada.

GENERAL OBJECTIVE: To verify the effectiveness of lymphedema treatment over a two-year period, in a group of women who underwent breast cancer surgery. Specific objective: To evaluate the volume of the treated arm at 6, 12, 18 and 24 months after the lymphedema treatment. METHOD: The participants were attended at a specialized rehabilitation service. They underwent lymphedema treatment consisting of manual lymphatic drainage and functional compressive bandaging and received guidance regarding self-care, self-massage, elastic sleeve use and exercise. They were evaluated by means of limb volume measurement at the following times: thirty-six women after the intensive phase, twenty-two after six months, fifteen after twelve months, six after eighteen months and eleven after twenty-four months. Adherence to the self-care strategies and exercises was evaluated by means of a questionnaire. Statistical tests were used to seek correlations between lymphedema reduction and some factors such as age, schooling, lymphedema grade, type of surgery, etc. RESULTS: There was a reduction in lymphedema and this was maintained throughout the period analyzed. There was no correlation between lymphedema reduction and factors such as age, marital status, schooling, type of surgery, body mass index, lymphedema grade, radiotherapy, circumference, arterial hypertension or joint limitation. Moreover, most of the women did not adhere to the self-care strategies, arm exercises, self-massage and elastic sleeve use. CONCLUSION: It is important to conduct new studies, for systematic and controlled analysis of the role of this guidance in relation to lymphedema evolution following the intensive phase of treatment.

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As MRI contrast agents, more hydrophobic molecules reportedly accumulate in the liver and thus are potentially useful as liver MRI contrast agents. In this study, a generation-4 polypropylenimine diaminobutane dendrimer (DAB-Am64), which is expected to be more hydrophobic than the generation-4 polyamidoamine dendrimer (PAMAM-G4D), was used to synthesize a conjugate with 2-(p-isothiocyanatobenzyl)-6-methyl-diethylenetriaminepentaacetic acid (1B4M) [DAB-Am64-(1B4M-Gd)(64)] for complexing Gd(III) ions. This DAB conjugate quickly accumulated in the liver and its characteristics were studied and compared with those of a PAMAM conjugate [PAMAM-G4D-(1B4M-Gd)(64)], which is known to be a useful vascular MRI contrast agent, in regard to its availability as a liver MRI contrast agent. DAB-Am64-(1B4M-Gd)(64) accumulated significantly more in the liver and less in blood than PAMAM-G4D-(1B4M-Gd)(64) (P < 0.001). Contrast-enhanced MRI with DAB-Am64-(1B4M-Gd)(64) was able to homogeneously enhance liver parenchyma and visualize both portal and hepatic veins of 0.5 mm diameter in mice. In conclusion, DAB-Am64-(1B4M-Gd)(64) is a good candidate for a liver MRI contrast agent.

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To enhance the effect of radio-immunotherapy for solid cancers, whole-body mild hyperthermia was added, and its effects on the pharmacokinetics of radiolabelled antibody, outcome of radio-immunotherapy, and radiosensitivity of the tumour were investigated. Nude mice bearing human colon cancer xenografts were heated to 40 degrees C for 3 or 6 h. After heating, mice received intravenous (i.v.) injections of [131I]-labelled anti-carcinoembryonic antigen (CEA) monoclonal antibody. Although 6-h heating did not alter the biodistribution of the radiolabelled antibody, and alone did not show any therapeutic effect on tumour growth, when combined with radio-immunotherapy, the therapeutic effect on tumour growth was significantly enhanced. Three-hour heating also significantly enhanced the effect of radio-immunotherapy. Colony formation assay showed that the radiosensitivity of the tumour was significantly enhanced after heating, which was achieved by a reduction of the hypoxic fraction of the tumour. In conclusion, the addition of whole-body mild hyperthermia significantly enhanced the therapeutic effect of radio-immunotherapy by increasing the radiosensitivity of the tumour.

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OBJECTIVE: Recurrence is often a major problem for patients who have undergone surgery for ovarian cancer. This prospective study was undertaken to evaluate the clinical contribution of positron emission tomography (PET) using (18)F-fluorodeoxyglucose (FDG) for recurrent ovarian cancer. SUBJECTS AND METHODS: Twenty-four women who had undergone surgery or chemoradiotherapy for histopathologically proven ovarian cancer were enrolled in this study. Ovarian cancer was thought to have recurred in 12 of these women because of evidence on conventional imaging modalities or tumor marker measurements (group A). Clinical findings for the remaining 12 women showed them to be disease-free (group B). PET findings for the women were compared with the final diagnoses obtained by histopathology or by clinical follow-up. The clinical contribution of PET was assessed by evaluating whether PET yielded information complementing the findings of conventional modalities and by examining its impact on treatment. RESULTS: PET gave valuable information for seven of 12 patients in group A in addition to the information obtained from findings on conventional imaging, and treatment was affected in five patients. On the other hand, in group B, additional information was obtained in only three of 12 patients, and treatment of only one patient was affected. Overall sensitivity, specificity, and accuracy of conventional imaging modalities were 72.7%, 75.0%, and 73.3%, respectively, and these rates improved to 92.3%, 100.0%, and 94.4%, respectively, by considering both conventional imaging modalities and PET findings. CONCLUSION: Our preliminary data suggest that whole-body PET with FDG can be a complementary modality for following up patients who have had ovarian cancer, especially patients believed to be at risk for recurrence.

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OBJECTIVES: The present study was designed to compare the absolute myocardial blood flow (MBF) after intravenous dipyridamole infusion with that during dobutamine-atropine administration in normal healthy male volunteers. BACKGROUND: Both safety and usefulness of dobutamine-atropine stress in myocardial perfusion imaging have been reported. However, no information exists on whether the magnitude ofhyperemia achieved with dipyridamole and dobutamine-atropine is comparable. METHODS: Myocardial blood flow was measured with positron emission tomography and 15O-labeled water in 20 healthy young men (23 +/- 3 years) 1) at baseline, 2) after dipyridamole infusion (0.56 mg/kg over 4 min), and 3) during dobutamine (40 microg/kg/min) and atropine (0.25 to 1.0 mg) infusion. RESULTS: The MBF was significantly increased during dipyridamole infusion and during dobutamine-atropine stress compared with at rest (4.33 +/- 1.23 and 5.89 +/- 1.58 vs. 0.67 +/- 0.16 ml/min/g, respectively, p < 0.0001). Moreover, dobutamine-atropine infusion produced greater MBF compared with dipyridamole (p = 0.0011), while coronary vascular resistance did not differ significantly after dipyridamole administration and during dobutamine-atropine infusion (17.6 +/- 7.9 vs. 18.6 +/- 5.6 mm Hg/[ml/min/g], respectively). CONCLUSIONS: Near maximal coronary vasodilatation caused by dipyridamole is attainable using dobutamine and atropine in young healthy volunteers. Dobutamine in conjunction with atropine is no less effective than dipyridamole in producing myocardial hyperemia.

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Regarding recurrence as a possibility in the lives of women with breast cancer, this work aimed at identifying how they construct the meaning of such possibility from their own existence. The study was based on the conceptions of symbolic interactionism and the content analysis of interviews with 12 mastectomized women was used. The possibility of recurrence was present in the lives of the women under study. It was configured by the uncertainty that they experienced and represented in the thematic units identified in their accounts when they stated to be "living with a stigmatizing disease", "experiencing a negative feeling" and "facing prejudice".

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The purpose of this retrospective study was to elucidate the fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) findings in autoimmune-related pancreatitis (AIP), which is a reversible chronic pancreatitis with an autoimmune cause. The study group comprised six patients with clinically diagnosed AIP. After 370 MBq (10 mCi) of FDG had been injected intravenously, the abdomen and/or the whole body was scanned at 1 h post injection in all patients, and scanning was repeated at 2 h in four patients. PET findings were evaluated visually and/or semiquantitatively using the standardized uptake value (SUV). In four of the six patients, PET demonstrated intense uptake in the whole pancreas, which appeared swollen on computed tomography, and the accumulation increased with time in three patients. In one patient, intense focal uptake in the pancreatic head was observed, and the accumulation decreased over time. In the remaining patient, no abnormal accumulation in the pancreas was observed. Follow-up PET scanning after steroid therapy was performed in three patients, and intense FDG uptake was no longer observed. Our preliminary data show that AIP can cause intense FDG uptake in the pancreas. This fact, and the benign status of the condition, should be kept in mind when making a diagnosis with FDG-PET in patients with pancreatic disorders.

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Actions to stimulate breastfeeding are directed to assist children's needs and do not contemplate woman in her specificities. The present study aimed at understanding the meanings women give to their experiences and demands in the practice of breastfeeding. 20 women that were experiencing breastfeeding for the first time were interviewed. Data analysis were based on the feminist theory. Authors found breast feeding as a feminine process socially determined. Women showed accommodation as they felt the act of breast feeding as donation, a sacrifice and dedication as well as resistance when they justified weaning affirming the lack of physiological capacity for breastfeeding.

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Dipyridamole (DIP), a coronary vasodilator, presents coactivator activity for a number of antitumor drugs as well as antioxidant activity in membrane systems. DIP and derivatives interact with membrane systems such as micelles, phospholipid monolayers and vesicles. The antioxidant effect of DIP and several derivatives upon iron-induced lipoperoxidation on mitochondria has been reported and a good correlation between the hydrophobicity and their protective effect was found (M.F. Nepomuceno et al., Free Radic. Biol. Med., 23 (1997) 1046-1054). In the present work an effort is made to better understand the role of DIP as inhibitor of Fe2+-induced lipid peroxidation in mitochondria. At low concentration, no significant effect on either state IV or state III respiration was found, discarding a possible direct interaction of DIP or RA-25 with the peripheral benzodiazepine receptor. The association constants for DIP and RA-25 in mitochondria were estimated, being 0.7 (mg/ml)-1 for DIP and 0.2 (mg/ml)-1 for RA-25. Oxygen consumption studies in the presence of FeSO4 showed that the antioxidant effect of DIP or RA-25 did not involved the initial step of Fe2+ oxidation. Our data strongly support the hypothesis that the antioxidant effect of both DIP and RA-25 is related to their partition in the lipid phase of the mitochondrial membrane and not to a specific interaction with membrane proteins. This protection may be due either to a direct inhibition of the propagation steps or a scavenger effect on the radicular species that would trigger the peroxidative process.

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The objective of the present study was to determine the main difficulties and problems experienced by patients submitted to sealed internal radiotherapy as well as to provide guidance for nurses to better perceive the difficulties experienced by the patients and act as an element of support while giving care. The problems and difficulties observed and reported by the patients were mainly related to the impositions of treatment, such as isolation, prohibition of visits, hospitalization, bed confinement, restriction of movements, use of the intracavity system, measures of radiological protection, use of a delay bladder tube, and limited personal hygiene. Fear related to treatment and anesthesia, partial or absent orientation and skin lesions were the complaints voiced by most of the patients in the present study. The role of the nurse is important in planning nursing care in sealed internal radiotherapy, especially when nurses understand the problems and difficulties experienced by women submitted to this treatment.

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This investigation is part of a transcultural research project on women and health, which has as its conceptual framework women's life experiences. This research is qualitative in nature, and the methodology utilized is a content analysis of the documented discourses of a group of lower class women in Ribeirão Preto (SP). The results demonstrate that for these women, health is much more than the absence of disease". Their health concerns are biological, interpersonal, social and economic in nature, and are based more upon their personal experiences and social perceptions than on the concept of health and disease. The importance of this research is its relevance for quality nursing care which takes into consideration the many aspects of being a woman.

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The activity of angiotensin I-converting enzyme (ACE, EC 3.4.15.1), measured using Hip-His-Leu as substrate, was determined in the developing chick retina, and in monolayer and aggregate cultures of embryonic retinal cells. ACE specific activity in chick retinal homogenate increased 86-fold from embryonic day 13 until the 7th post-hatching day. The development of ACE activity occurred in parallel with that reported for synapse and photoreceptors. ACE activity expression in aggregates, but not in monolayer culture, was similar to that observed in the developing retina in ovo. At culture, day 13, ACE specific activity was 11.8-fold higher in the aggregate than in the dispersed cell culture, and was comparable to that in a 21-day-old embryonic intact retina. Our results suggest that histotypic association of retinal cells during development may be an important event controlling the expression of ACE activity in the CNS.

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The time course of dipeptidase activity and the effect of p-mercuribenzoate (PCMB) on the subestimation of the fluorometric determination of angiotensin-converting enzyme (ACE, EC 3.4.15.1) during development was studied. ACE and dipeptidase activities were measured fluorometrically in homogenates of the developing chick retina using Hip-His-Leu and His-Leu as substrates, respectively, both either in the presence or in the absence of 1 mM PCMB. ACE activity was inhibited by captopril (IC50 1.7 nM), MK 422 (IC50 4.8 nM), BPP9a (IC50 0.25 microM) and BPP5a (IC50 1.2 microM), thus suggesting that avian retinal ACE catalytically resembles the mammalian enzyme. Dipeptidase activity varied 3.4-fold throughout development, leading to a large and variable (28-83%) subestimation of ACE activity during chick retina ontogenesis. PCMB (1 mM) inhibited 67-94% dipeptidase activity during development, thus greatly reducing any subestimation of ACE activity determination during the development of the chick retina.

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